A method for preparing chlorine gas through catalytic oxidation of hydrogen chloride is carried out by one-time hydrogen chloride feeding and multi-stage oxygen feeding, one-time oxygen feeding and multi-stage hydrogen chloride feeding, or both, returning a product gas stream without separation thereof, and optionally carrying out heat insulation means. In the present invention, excessive reaction heat concentration is prevented, therefore, the method of the present invention is a chlorine gas recovery method implemented through the Deacon catalytic oxidation of hydrogen chloride that may be industrialized.

The invention relates to a process for preparation of chlorine from hydrogen chloride comprising circulating a liquid melt comprising copper ions Cu.sup.n+ with n being a number in the range from 1 to 2, alkali cations and chloride ions Cl in a reactor system comprising three bubble lift reactors I, II and III, each comprising a reaction zone i, ii and iii respectively, wherein: ?(a) in the reaction zone i of the first bubble lift reactor I, a liquid melt comprising copper ions Cu.sup.n+, alkali cations and chloride ions Cl is contacted with oxygen at a temperature in the range from 395 to 405? C. so that the molar ratio Cu.sup.n+:Cu.sup.+ in the liquid melt increases, obtaining a liquid melt having an increased molar ratio Cu.sup.n+:Cu.sup.+ ?(b) the liquid melt obtained in (a) is circulated to the reaction zone ii in the second bubble lift reactor II, where the liquid melt is contacted with hydrogen chloride at a temperature in the range from 395 to 405? C. so that water is formed, obtaining a liquid melt being enriched in chloride anions (CI-) compared to the liquid melt obtained according to (a); ?(c) circulating the liquid melt obtained in (b) to the reaction zone iii in the third bubble lift reactor III, which is operated at a temperature in the range from 420 to 430? C. so that chlorine (Cl.sub.2) is formed, wherein Cl.sub.2 is removed from the reaction zone iii and the third bubble lift reactor III respectively in gaseous form, leaving a liquid melt depleted of Cl-compared to the liquid melt obtained according to (b). The invention further relates to a reactor system comprising three bubble lift reactors I, II and III.

The invention relates to a process for preparation of chlorine from hydrogen chloride comprising circulating a liquid melt comprising copper ions Cu.sup.n+ with n being a number in the range from 1 to 2, alkali cations and chloride ions Cl in a reactor system comprising three bubble lift reactors I, II and III, each comprising a reaction zone i, ii and iii respectively, wherein: ?(a) in the reaction zone i of the first bubble lift reactor I, a liquid melt comprising copper ions Cu.sup.n+, alkali cations and chloride ions Cl is contacted with oxygen at a temperature in the range from 395 to 405? C. so that the molar ratio Cu.sup.n+:Cu.sup.+ in the liquid melt increases, obtaining a liquid melt having an increased molar ratio Cu.sup.n+:Cu.sup.+ ?(b) the liquid melt obtained in (a) is circulated to the reaction zone ii in the second bubble lift reactor II, where the liquid melt is contacted with hydrogen chloride at a temperature in the range from 395 to 405? C. so that water is formed, obtaining a liquid melt being enriched in chloride anions (CI-) compared to the liquid melt obtained according to (a); ?(c) circulating the liquid melt obtained in (b) to the reaction zone iii in the third bubble lift reactor III, which is operated at a temperature in the range from 420 to 430? C. so that chlorine (Cl.sub.2) is formed, wherein Cl.sub.2 is removed from the reaction zone iii and the third bubble lift reactor III respectively in gaseous form, leaving a liquid melt depleted of Cl-compared to the liquid melt obtained according to (b). The invention further relates to a reactor system comprising three bubble lift reactors I, II and III.

The invention relates to known catalysts which contain cerium or other catalytically active components for producing chlorine by means of a catalytic gas phase oxidation of hydrogen chloride with oxygen. A catalyst material is described for producing chlorine by means of a catalytic gas phase oxidation of hydrogen chloride with oxygen, wherein the catalyst comprises at least oxide compounds of the cerium as active components and zirconium dioxide microparticles as the carrier components, and the catalyst is characterized by a particularly high yield, measured in kg.sub.Cl2/kg.sub.KA T.Math.h, based on the mass of the catalyst.

The invention relates to known catalysts which contain cerium or other catalytically active components for producing chlorine by means of a catalytic gas phase oxidation of hydrogen chloride with oxygen. A catalyst material is described for producing chlorine by means of a catalytic gas phase oxidation of hydrogen chloride with oxygen, wherein the catalyst comprises at least oxide compounds of the cerium as active components and zirconium dioxide microparticles as the carrier components, and the catalyst is characterized by a particularly high yield, measured in kg.sub.Cl2/kg.sub.KA T.Math.h, based on the mass of the catalyst.

The present invention relates to a method for chlorination and dehydrogenation of ethane, comprising: mixing and reacting a low-melting-point metal chloride with C.sub.2H.sub.6, such that the low-melting-point metal chloride is reduced to a liquid-state low-melting-point metal, and the C.sub.2H.sub.6 is chlorinated and dehydrogenized to give a mixed gas containing HCl, C.sub.2H.sub.6, C.sub.2H.sub.4, C.sub.2H.sub.2 and C.sub.2H.sub.3Cl. In the method, the low-melting-point metal chloride is used as a raw material for chlorination and dehydrogenation, and the low-melting-point metal produced after the reaction is used as an intermediate medium. The method has the characteristics of simple process, low cost and high yield. Moreover, some acetylene and vinyl chloride can be produced as by-products at the same time when the ethylene is produced, by controlling the ratio of ethane to the chloride as desired in production.

A catalyst is a hydrochloric acid oxidation catalyst for oxidizing hydrochloric acid. The catalyst includes a carrier, and copper, an alkali metal, and a rare earth element that are carried by the carrier. The catalyst is composed of particles. A rate of change in crushing strength before and after heating is 0% or more and 40% or less.

[00001]$\mathrm{Rate}\mathrm{of}\mathrm{change}\mathrm{in}\mathrm{crushing}\mathrm{strength}\mathrm{before}\mathrm{and}\mathrm{after}\mathrm{heating}=\left[I1-I0\right]/I0100\left(\%\right)$ I0: Crushing strength before heating I1: Crushing strength after heating

A catalyst is a hydrochloric acid oxidation catalyst for oxidizing hydrochloric acid. The catalyst includes a carrier, and copper, an alkali metal, and a rare earth element that are carried by the carrier. The catalyst is composed of particles. A rate of change in crushing strength before and after heating is 0% or more and 40% or less.

[00001]$\mathrm{Rate}\mathrm{of}\mathrm{change}\mathrm{in}\mathrm{crushing}\mathrm{strength}\mathrm{before}\mathrm{and}\mathrm{after}\mathrm{heating}=\left[I1-I0\right]/I0100\left(\%\right)$ I0: Crushing strength before heating I1: Crushing strength after heating

The invention relates to an improved process for making available the coproduct hydrogen chloride obtained in the preparation of an isocyanate by phosgenation of the corresponding amine for a desired subsequent use (i.e. a chemical reaction), in which part of the total hydrogen chloride obtained is isolated in gaseous form at a pressure which is higher than the pressure desired for the subsequent use of the hydrogen chloride by lowering the pressure of the crude product from the phosgenation and the remaining part of the total hydrogen chloride obtained is separated off at a pressure lower than that desired for the subsequent use from the liquid crude product from the phosgenation remaining after lowering of the pressure and is subsequently compressed to a pressure which is higher than that desired for the subsequent use, and in which the two hydrogen chloride streams obtained in this way are, preferably together after having been combined, purified so as to give a purified hydrogen chloride at a pressure which is higher than the pressure desired for the subsequent use.

The invention relates to an improved process for making available the coproduct hydrogen chloride obtained in the preparation of an isocyanate by phosgenation of the corresponding amine for a desired subsequent use (i.e. a chemical reaction), in which part of the total hydrogen chloride obtained is isolated in gaseous form at a pressure which is higher than the pressure desired for the subsequent use of the hydrogen chloride by lowering the pressure of the crude product from the phosgenation and the remaining part of the total hydrogen chloride obtained is separated off at a pressure lower than that desired for the subsequent use from the liquid crude product from the phosgenation remaining after lowering of the pressure and is subsequently compressed to a pressure which is higher than that desired for the subsequent use, and in which the two hydrogen chloride streams obtained in this way are, preferably together after having been combined, purified so as to give a purified hydrogen chloride at a pressure which is higher than the pressure desired for the subsequent use.